The article assumes the command-line utilities are to be used on a *nix system (e.g. GNU/Linux, BSD, Mac OS X, Unix), and it will frequently reference to common tools on such systems.

If you are only going to consider *nix then IMHO, you are a mission that is doomed to failure.

If you are going to provide guidlines on what should go into a decent CLI then you MUST consider other systems. By failing to do that you are setting out on a marathon with one leg in plaster.

For example,
As I stated before the hierarchical help system used in the VMS DCL environment is wonderful. It makes a flat help system redundant. So why can't to divorce the help system from the application?
Supply the binary and the help file that is accessible through the generic shell help widget (or whatever).

Lets get away from the limitations imposed on us by the Original Unix devs who were working on very slooooowwwww devices (eg Teletypes, ASR33, 110Baud). Times have changed.
So should the command line.

I hate info pages. I find manpages much easier to manage. It's for this reason that when I find documentation or guides or books online, I always go for the "entire manual in a single PDF/HTML page" option instead of the piece-by-piece option. It's much easier to scroll around or use search than navigate a hierarchy that someone else devised and that may not actually organize things in a way that helps *you* find what you need.